In the field of horology, and more particularly of wristwatches, it is known to secure the ends of a wristlet to the middle part of the watch case using a hinge means. For leather wristlets formed of two distinct strands, this hinge means generally takes the form of a pair of horns or fastenings to which there is fixed a bar, around which there is wound the end of the wristlet strand, which can thus pivot relative to the middle part. For rubber wristlets, variants are often proposed for fastening using central claws which are arranged between the horns and are provided with through holes for the bar to pass through. In this case, the end of the wristlet fastening has a particular cut-out in the form of slots.
Other fastening methods using screws or rivets are also known.
The drawback of these fastening methods is that the holes made in the wristlet for the bar, screws or rivets to pass through form stress raisers and thus reduce the mechanical resistance of the wristlet to traction. Further, for wristlets made of synthetic fabric for example, it is impossible to make these holes in the edge.
Consequently, alternative solutions have been proposed for retaining the end of the wristlet strand, dispensing with the use of holes in the end of the wristlet strand, particularly for wristlets made of synthetic fabric or plastic. EP Patent No 0246449 by the Applicant proposes, for example, to insert the end of the strand into a housing and to hold it therein using a pin whose shape matches that of a channel portion arranged in the wristlet.
This type of solution has the drawback, however, of not being suitable for cases made of plastic material, whose creep is liable sooner or later to release the end of the strand and the pin from their respective housings because of the constant pressure exerted by the pin on the case. Further, no axial retaining means other than friction forces is provided to prevent the pin from moving on its axis. Thus, it is impossible to ensure that the pin is permanently secured to the case, particularly if the strand is pulled off, which presents a risk for products intended for children, such as, for example, Flik Flak™ watches, since children could then swallow the pin.
There is consequently a need for a wristwatch provided with a device for assembling the strand which is free of these known limitations.